Viral transmission and evolution dynamics of SARS-CoV-2 in shipboard quarantine.

OBJECTIVE: To examine transmission and evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in shipboard quarantine of the Diamond Princess cruise ship. METHODS: We obtained the full SARS-CoV-2 genome sequences of 28 samples from the Global Initiative on Sharing All Influenza Data database. The samples were collected between 10 and 25 February 2020 and came for individuals who had been tested for SARS-CoV-2 during the quarantine on the cruise ship. These samples were later sequenced in either Japan or the United States of America. We analysed evolution dynamics of SARS-CoV-2 using computational tools of phylogenetics, natural selection pressure and genetic linkage. FINDINGS: The SARS-CoV-2 outbreak in the cruise most likely originated from either a single person infected with a virus variant identical to the WIV04 isolates, or simultaneously with another primary case infected with a virus containing the 11083G > T mutation. We identified a total of 24 new viral mutations across 64.2% (18/28) of samples, and the virus evolved into at least five subgroups. Increased positive selection of SARS-CoV-2 were statistically significant during the quarantine (Tajima's D: -2.03, P < 0.01; Fu and Li's D: -2.66, P < 0.01; and Zeng's E: -2.37, P < 0.01). Linkage disequilibrium analysis confirmed that ribonucleic acid (RNA) recombination with the11083G > T mutation also contributed to the increase of mutations among the viral progeny. CONCLUSION: The findings indicate that the 11083G > T mutation of SARS-CoV-2 spread during shipboard quarantine and arose through de novo RNA recombination under positive selection pressure.

Prolonged viral shedding and new mutations of COVID-19 could complicate the control of the pandemic.

The studies of coronavirus disease 2019 (COVID-19) have mainly focused on epidemiological and clinical features of patients, but transmission dynamics of SARS-CoV-2 virus after patients have recovered is still poorly understood. Here we report a case with prolonged viral shedding of COVID-19 in Kaohsiung, Taiwan. This patient started to show myalgia and malaise in Wuhan, and the onset of the fever was on days 7-14 of the illness. All clinical and radiological results returned to normal after day 26, however, viral shedding was still evident 14 days later. Sequence analysis of the genome of the Taiwanese SARS-CoV-2 isolate from this patient reveals new mutations in viral replicase and ORF3a, indicating that COVID-19 evolves very quickly. Prolonged viral shedding and new mutations in the viral genome could potentially complicate the control of the COVID-19 pandemic.

Family members' concerns about relatives in long-term care facilities: Acceptance of visiting restriction policy amid the COVID-19 pandemic.

AIM: The policy enforcing visiting restriction during the COVID-19 pandemic may cause feelings of social isolation among residents in long-term care facilities. This study aimed to explore family members' concerns for their relatives during the lockdown period, assess their level of acceptance of the visiting restriction policy and determine the associated factors. METHODS: From the 156 family members interviewed, demographic data, satisfaction with overall care quality, worry and concerns for their relatives, acceptance of the visiting restriction and arrangement for the residents if cluster infections occur in the facility were recorded. RESULTS: Among the members interviewed, 83 (53.2%) were men; mean age of members was 56.3 ± 9.8; most were offspring of residents in the facility (n = 121, 77.6%), most visited the residents at least once a week (n = 113, 72.4%) before the lockdown. The most common concerns of the family members for their relatives were psychological stress (38.5%), followed by nursing care (26.9%) and daily activity (21.1%). Nearly 84.6% of those interviewed accepted the visiting restriction policy, and a higher satisfaction rating independently associated with acceptance of the visiting restriction policy (odds ratio 2.15). CONCLUSIONS: During the lockdown period, staff members should provide more psychological information about residents to their family members. Higher satisfaction rating was found to be independent of the acceptance of the visiting restriction policy. Therefore, good quality of care of the facility wins the trust of family members, and this might mitigate the tension between the family members and staff during a major crisis. Geriatr Gerontol Int ••; ••: ••-•• Geriatr Gerontol Int 2020; 20: 938-942.